EVALUATION OF THE EFFECTS OF SOIL COMPACTION ON HYDROLOGY AND SOIL EROSION

土壤压实对水文和土壤侵蚀影响的评价

• 批准号: RGPIN-2014-05506
• 负责人: Gumiere, Silvio
• 金额: $ 1.89万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=681483
• 关键词: EVALUATION; EFFECTS; SOIL; COMPACTION; HYDROLOGY

Soil compaction presents a major issue in modern day farming, and it is suspected that this process is to a large extent responsible for losses in productivity associated with yield reduction in precision agriculture. Commonly defined as the process by which soil grains are rearranged, soil compaction decreases the void between them and brings them into closer contact. The spatial extent of compacted soil is estimated at 68 million hectares worldwide, and in Europe alone soil compaction is responsible for the degradation of 33 million hectares of arable land. Similar problems have been reported in Canada and the USA.*Although compaction is viewed as one of the severest environmental problems in conventional agriculture, it is also the most difficult type of degradation to identify because the symptoms are not always apparent at the surface. Soil compaction reduces infiltration rates, which leads to increased runoff, enhanced erosion and loss of nutrients and pesticides to surface water. It is very well possible that the spatial distribution of compacted areas alters hydrological and sediment connectivity. In addition, reduced infiltration indirectly affects the efficiency of surface and subsurface drainage systems and increases flood risk. Therefore, in order to prevent damage and rehabilitate affected areas, it is essential to develop more advanced modeling tools, create mapping tools, and optimize tillage practices and agricultural machinery.*The long-term objective of the proposed research program is to increase our understanding of how the spatial distribution of soil compaction affects the hydrology and soil erosion at the watershed scale. Outcomes will provide a solid scientific support for improving regulatory government policies related to the application of beneficial management practices (BMPs), and establish methods of identifying contamination sources with better precision.*Short-term objectives of this research program are: (i) to increase our comprehension of the effects of soil compaction on runoff production and erosion at the scale of the soil pedon; (ii) to understand the spatially distributed impact of compacted areas on hydrological and sedimentological connectivity at the watershed scale; and (iii) based on the findings of objectives (i) and (ii), to develop a distributed water erosion model able to account for the effects of soil compaction on watershed hydrological and sedimentological connectivity.*These research program will significantly improve our understanding on how soil compaction contributes to changes in watershed hydrology. Addressing this issue is of paramount importance to ongoing agricultural and earth science research because very few studies to date have attempted to illustrate how soil compaction can influence diffuse and concentrated sediment and nutrient transport during storm events. Research of this topic is essential for developing management strategies in areas where sediment and nutrient losses are significant and present serious risks for the quality of surface waters. However, the manner in which connectivity and associated nutrient and sediment transport are modified by the process of soil compaction remains unclear and may be specific to each watershed. For Canada, Outcomes will provide a solid scientific support for improving regulatory government policies related to the application of (BMPs), and establish new methods for the identification of contamination sources of agricultural watersheds with better precision.

土壤压实是现代农业中的一个主要问题，人们怀疑这个过程在很大程度上导致了精准农业产量下降导致的生产力损失。通常定义为土壤颗粒重新排列的过程，土壤压实减少了它们之间的空隙并使它们更紧密地接触。全球压实土壤的空间范围估计为 6800 万公顷，仅在欧洲，土壤压实就造成了 3300 万公顷耕地的退化。加拿大和美国也报告了类似的问题。*虽然压实被视为传统农业中最严重的环境问题之一，但它也是最难识别的退化类型，因为其症状并不总是在表面上显现出来。土壤压实降低了渗透率，从而导致径流增加、侵蚀加剧以及地表水中养分和农药的流失。 压实区域的空间分布很可能改变水文和沉积物的连通性。此外，渗透减少间接影响地表和地下排水系统的效率并增加洪水风险。因此，为了防止破坏和恢复受影响地区，有必要开发更先进的建模工具，创建绘图工具，并优化耕作方法和农业机械。*拟议研究计划的长期目标是增加我们的了解研究土壤压实的空间分布如何影响流域尺度的水文和土壤侵蚀。结果将为改善与有益管理实践（BMP）应用相关的政府监管政策提供坚实的科学支持，并建立更精确地识别污染源的方法。*该研究计划的短期目标是：（i）加深我们对土壤压实对土壤径流产生和土壤侵蚀影响的理解； (ii) 了解压实区对流域尺度水文和沉积学连通性的空间分布影响； (iii) 基于目标 (i) 和 (ii) 的结果，开发分布式水侵蚀模型，能够解释土壤压实对流域水文和沉积学连通性的影响。*这些研究计划将显着提高我们的理解关于土壤压实如何影响流域水文学的变化。解决这个问题对于正在进行的农业和地球科学研究至关重要，因为迄今为止很少有研究试图说明土壤压实如何影响风暴事件期间的扩散和集中沉积物以及养分输送。该主题的研究对于在沉积物和养分损失严重并对地表水质量构成严重风险的地区制定管理策略至关重要。然而，土壤压实过程改变连通性以及相关养分和沉积物运输的方式仍不清楚，并且可能针对每个流域。对于加拿大来说，成果将为完善与BMP应用相关的政府监管政策提供坚实的科学支持，并建立更精确地识别农业流域污染源的新方法。